March 29, 2013 — Fisheries should be managed so that they are profitable, otherwise fishermen won’t go out to fish. And fishing for maximum sustainable yield, which is a main criterion of the EU’s revised Common Fisheries Policy, is not the best way to achieve this objective.
So said Professor Sidney Holt when giving one of the Buckland Foundation’s annual lectures in March. “The value of the catch has to be more than the cost of catching it. Setting TACs (total allowable catches) is the worst possible way to manage a fishery.
“You don’t just use the brakes when driving a car. You have to manage the input not the output, which depends on recruitment [to the fishery].” The recruitment number can be the most variable, Holt said. “It can change by a factor of 100 year to year.”
Regarded as one of the founders of fishery science, Holt was speaking on the theme, “Why, or why not, maximum sustainable yield (MSY)? Contemporary thoughts on the rational management of fisheries” at Fishmongers’ Hall in London.
Although MSY forms a major constituent of the revisions now being sought for the CFP, the concept had first been introduced by the U.S. government at a conference in 1949 as a management objective for stopping Japanese fishing vessels coming into its waters to catch salmon.
There were no territorial waters in those days, Holt said, but added that the U.S. government sought to claim that it was fully utilizing the resources within what became its 200-mile limit or exclusive economic zone.
Maximizing yields using surplus production models is an unscientific method of managing fish populations, according to Holt. “You can’t use it to take account of selectivity. You’re catching too many fish when they’re young. This is the issue.
“You’ve got to look at the relationship between growth and death. How much more [death] is caused by fishing than nature?”
Ian Boyd, who preceded Holt as Buckland Professor for 2012/13, and spoke after him, agreed that there is little justification for the maximization of yield approach.
“If MSY is to be used then make it a limit not a target,” said Boyd.
Boyd went on to say that in his view fishing for MSY also ignores fundamental aspects of the ecosystem such as the need to leave enough fish in the sea for other parts of the food chain including mammals and seabirds. To do this means reducing the proportion of the fish stocks that is harvested.
Both speakers agreed that fishing in European waters should be reduced. Less fishing effort would mean more profit for those left in the fishery, and it would also provide a better balance between the components of the food chain that are harvested by fishermen, mammals and birds.
Read the full opinion piece at SeafoodSource.com